In a film forming apparatus in which a film formation object is subjected to film formation while passing through a position opposed to a sputter target, if the size of the film formation object is large relative to the target, the film fails to be formed on the outer periphery side, and the film thickness distribution is degraded. On the other hand, if the size of the film formation object is small relative to the target, the amount of film attached to portions other than the film formation object in the vacuum chamber increases, and hence the film formation efficiency decreases. Furthermore, attached matter in the vacuum chamber, if stripped off, contaminates the film formation object, and to prevent this, the inside of the vacuum chamber needs to be further cleaned, which requires time and effort.
Patent Document 1 discloses performing sputtering while a sputter cathode holding a target is rotated with respect to substrates, or performing sputter film formation on the substrates for a prescribed time with the sputter cathode stopped at a prescribed position, followed by rotating the sputter cathode to change its position and performing sputter film formation again on the substrates.
However, in Patent Document 1, as shown in FIG. 2 thereof, one circular target is held on the sputter cathode, but the target is not configured to simultaneously cover all the regions subjected to film formation (entire surface of two substrates). In the case of performing sputter film formation on the substrates while rotating the target about an axis eccentric to its center so that the entire surface of two substrates is opposed to the target, the sputter cathode is constantly rotated during film formation. This also needs to rotate the power supply line, and the refrigerant supply line for cooling the target. Thus, a special configuration is needed to prevent kinks and breaks due to these rotations.    Patent Document 1: JP-A-2005-187830